Later CLs will switch to these functions, and eventually the
CreateMediaChannel will be deprecated and removed.
Bug: webrtc:13931
Change-Id: I4c5ab89659a47a501728cac217bb1a877fa50047
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/307800
Reviewed-by: Tomas Gunnarsson <tommi@webrtc.org>
Commit-Queue: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#40221}